Show HN: NFC Energy-Harvesting PCB Business Card with an MCU

entrepy123 · 2026-08-30T23:06:54.000Z

Really cool. I'd love to be able to order cheap ones in packs of 5 or 10, with custom led colors/locations/sizes/brightness, fitting into a printed card...

yegle · 2026-08-30T22:45:20.000Z

For future PCB business card ideas: it would be dope if it can play audios.

Gemini says you can power a piezo buzzer (causing a small bump on a PCB) w/ NFC (just enough power to drive it) to play the modem dialup handshake audio.

badatnames · 2026-08-30T22:25:51.000Z

Look at that subtle off-white coloring, the tasteful thickness of it. Oh my God, it even has a schematic

danshagen · 2026-08-30T21:08:19.000Z

cool project, especially as a bachelor student of EE!

chews · 2026-08-30T21:38:45.000Z

Really great project, thanks for sharing and what a well done write-up! Also kudos for including the PCB, BOM, and code on GH with a permissive license.

thenthenthen · 2026-08-30T20:52:01.000Z

Nice write up!